Variable vane arm retention feature

Abstract

A variable vane actuation system of a gas turbine engine is provided. The variable vane actuation system comprising: a vane arm having a radially inward facing surface, a radially outward surface opposite the radially inward facing surface, a wedge projecting away from the radially inward facing surface, an aperture extending from the radially outward surface to the radially inward surface, and an interlocking feature located in the aperture and circumferentially opposite the wedge relative to the aperture; and a vane stem having a first end, a second end opposite the first end, a seat surface interposed between the first end and the second end, a primary portion extending from the first end to the seat surface, a secondary portion extending from the seat surface to the second end, and a stem notch configured to interlock with the interlocking feature of the vane arm.

What is claimed is: 
     
       1. A variable vane actuation system of a gas turbine engine, comprising:
 a vane arm having a radially inward facing surface, a radially outward surface opposite the radially inward facing surface, a wedge projecting radially outward from the radially outward facing surface of the vane arm, an aperture extending from the radially outward surface to the radially inward surface, and an interlocking feature located in the aperture and circumferentially opposite the wedge relative to the aperture; and 
 a vane stem having a first end, a second end opposite the first end, a seat surface interposed between the first end and the second end, a primary portion extending from the first end to the seat surface, a secondary portion extending from the seat surface to the second end, and a stem notch configured to interlock with the interlocking feature of the vane arm to prevent axial motion between the vane stem and the vane arm along an axis of the vane stem, 
 wherein the wedge and the vane arm are formed as a single piece comprising a unitary structure. 
 
     
     
       2. The variable vane actuation system of  claim 1 , further comprising:
 a locking nut having internal threads configured to mesh with external threads located on the primary portion of the vane stem; or 
 a bolt having external threads configured to mesh with internal threads located on the primary portion of the vane stem. 
 
     
     
       3. The variable vane actuation system of  claim 2 , wherein the stem notch is configured to interlock with the interlocking feature of the vane arm when the secondary portion is within the aperture, the radially outward surface of the vane arm is flush with the seat surface of the vane stem, and the locking nut is installed on the primary portion of the vane stem. 
     
     
       4. The variable vane actuation system of  claim 1 , wherein the vane stem further comprises:
 a radially upper shoulder located in the secondary portion proximate the seat surface; and 
 a radially lower shoulder located in the secondary portion and interposed between the radially upper shoulder and the second end, 
 wherein the stem notch extends from the upper shoulder to the radially upper shoulder to the radially lower shoulder. 
 
     
     
       5. The variable vane actuation system of  claim 1 , wherein the interlocking feature of the vane arm includes a notch in the aperture extending into the vane arm. 
     
     
       6. The variable vane actuation system of  claim 5 , wherein the notch in the aperture is located proximate the radially outward surface of the vane arm. 
     
     
       7. The variable vane actuation system of  claim 1 , wherein the interlocking feature of the vane arm includes a pin. 
     
     
       8. The variable vane actuation system of  claim 7 , wherein the pin is oriented perpendicular to the stem notch. 
     
     
       9. The variable vane actuation system of  claim 7 , wherein the pin is oriented parallel to the stem notch. 
     
     
       10. The variable vane actuation system of  claim 7 , wherein the pin extends through the aperture. 
     
     
       11. The variable vane actuation system of  claim 7 , wherein the pin extends partially into the aperture. 
     
     
       12. A gas turbine engine comprising:
 a vane system; and 
 a variable vane actuation system operably connected to the vane system, the variable vane actuation system comprising:
 a vane arm having a radially inward facing surface, a radially outward surface opposite the radially inward facing surface, a wedge projecting away radially outward from the radially outward facing surface of the vane arm, an aperture extending from the radially outward surface to the radially inward surface, and an interlocking feature located in the aperture and circumferentially opposite the wedge relative to the aperture; and 
 a vane stem having a first end, a second end opposite the first end, a seat surface interposed between the first end and the second end, a primary portion extending from the first end to the seat surface, a secondary portion extending from the seat surface to the second end, and a stem notch configured to interlock with the interlocking feature of the vane arm to prevent axial motion between the vane stem and the vane arm along an axis of the vane stem, 
 wherein the wedge and the vane arm are formed as a single piece comprising a unitary structure. 
 
 
     
     
       13. The gas turbine engine of  claim 12 , further comprising:
 a locking nut having internal threads configured to mesh with external threads located on the primary portion of the vane stem; or 
 a bolt having external threads configured to mesh with internal threads located on the primary portion of the vane stem. 
 
     
     
       14. The gas turbine engine of  claim 12 , wherein the vane stem further comprises:
 a radially upper shoulder located in the secondary portion proximate the seat surface; and 
 a radially lower shoulder located in the secondary portion and interposed between the radially upper shoulder and the second end, 
 wherein the stem notch extends from the upper shoulder to the radially upper shoulder to the radially lower shoulder. 
 
     
     
       15. The gas turbine engine of  claim 12 , wherein the interlocking feature of the vane arm includes a notch in the aperture extending into the vane arm. 
     
     
       16. The gas turbine engine of  claim 15 , wherein the notch in the aperture is located proximate the radially outward surface of the vane arm. 
     
     
       17. The gas turbine engine of  claim 12 , wherein the interlocking feature of the vane arm includes a pin. 
     
     
       18. The gas turbine engine of  claim 17 , wherein the pin is oriented perpendicular to the stem notch. 
     
     
       19. The gas turbine engine of  claim 17 , wherein the pin is oriented parallel to the stem notch. 
     
     
       20. The gas turbine engine of  claim 17 , wherein the pin extends through the aperture.